Bobfrommaine: Here you've raised another good point -- yes, airbags work poorly or not at all if the driver or passenger is incorrectly positioned. That's why GM fought airbags so hard in the early '90s, even after Chrysler had bags in 99% of their vehicles. For years, Dr. David Viano of GM tracked surveys and polls that suggested the public didn't understand airbag technology. "All the surveys said the same thing," Viano said in 1992. "The public thought airbags were magic and superior in their effectiveness to seat belts." GM believed that if drivers had airbags, they would stop using seat belts. Hopefully, drivers have figured it out at this point.

Bobfrommaine: Having seen an airbag deploy, I now have even greater respect for the danger faced by first responders. Regarding your comment about review of Newton's Laws: After seeing how little regard some drivers have for reaction and stopping distances, I have unfortunately concluded that some drivers are beyond help, no matter what we try to teach them.

That's a tough one, Ann. I can only back into the answer: Bigger vehicles with more energy absorption area in front don't use knee bags. That said, every vehicle uses driver and front passenger bags, no matter how much crash energy is absorbed by the structure.

Interestingly, we train for airbag deployment during an extrication. Air-bags deploy with significant force and do a good job of protecting the occupants from that ONE impact. Frequently the initial impact is not the one that causes the most injury and the airbags are useless for the second and third impact. Airbags are defined as a supplimentary restraint system; they suppliment the seat-belt! Modern high-end cars actually envelope the occupants in infalted bags; but - big BUT - they do-not-work if the occupant is out of position; leaned over opening the glove box, sitting with the seat leaned far back, etc.. I'm not sure the airbag is the answer to bad driving habits.

bob from maine, you've added an interesting and important perspective to this discussion. I agree about diligent, trained, and I might add awake and alert and not DUI, drivers. OTOH, while hearing about the dangers of accidental airbag deployment I haven't thought of what could happen to rescue personnel in that event.

When I was on the extrication team on my Fire Department we had an opportunity to sit in a vehicle model and have an airbag inflated in our faces. There is no mental method to properly prepare you for the inflation! Seat Belts and Air Bags have made vehicle crashes much more survivable, if only people would use them. Inadvertant deployment of air-bags was and remains a significant danger to Fire Department personnel. Imagine an air-bag inflating while a Fireman is leaning across the passenger seat trying to assist in extricating the driver! Self driving/accident avoiding cars cannot replace a well trained, dilligent driver. An accident, as defined as an unavoidable occurace, very seldom happens. Automobile crashes are mostly caused by driver inattention and poor judgement. A periodic review by drivers of Newton's laws of motion should be mandatory. Thank you, and good night!

Airbags have always been obsolete. It is not just that they are dangerously explosive and expensive, but that they don't work as well as permanent passive devices. Permanent harness or padded restraints not only are cheaper, but work multiple times, and don't have any of the dangers, such at knocking the driver off the steering wheel. A padded frontal restraint could be lowered each time you get into the vehicle, just like on an amusement park ride. That would not only save millions in costs, but tens of thousands of lives. Each seat should have its own padded permanent retraints. It is a matter of time before the public realizes how dangerous air bags really are.

Chuck, thanks for the input. I've been told by the materials manufacturers that newer materials are at least as crash-resistant as metals, and the data I've seen supports that. But it's good to know from the automotive design end of things that that's indeed the case. The second thing I was wondering was if the reduced volume from the earlier metal vehicles meant there needs to be more airbags, which it sounds like you are implying. Is that the case, even though newer vehicles have been redesigned to handle structural loads better?

Industrial workplaces are governed by OSHA rules, but this isn’t to say that rules are always followed. While injuries happen on production floors for a variety of reasons, of the top 10 OSHA rules that are most often ignored in industrial settings, two directly involve machine design: lockout/tagout procedures (LO/TO) and machine guarding.

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